In systems that utilize transducers for monitoring environmental conditions such as pressure and/or temperature, it is often desirable to determine the individual transducer identification (ID) information. The ID can be the serial number uniquely assigned to each transducer, and may be printed on the body of the transducer. Certain characteristics of the transducer are typically stored in a database (or look-up table) and are associated with the transducer serial number. The process of manually entering the serial numbers to retrieve the stored characteristic information is prone to human errors.
There are methods presently in use that allow an individual ID and other data to be associated with each transducer. For example, a system known as a Transducer Electronic Data Sheet (TEDS) includes a small memory chip that can be installed in each device and the memory can be addressed and read by an external reader using one or two additional conductors. The memory can store information besides the serial number, such as the part number, manufacturing date, last calibration date, pressure range, as well as individual coefficients which, when used with a polynomial function, may be used to reduce various errors associated with the transducer.
Transducers using TEDS have a limitation that they can be unreliable under certain conditions. For example, the TEDS electronics they may not survive high temperatures in excess of +125° C. Furthermore, the memory chip, being an active electronic device, may be susceptible to EMI, lightning or ESD. Another drawback to using memory chips for device ID is that, for certain applications, circuits that utilize digital and/or memory circuits need to be certified through a lengthy and costly procedure. There exists a need for systems and methods that can overcome these limitations and drawbacks.